Zhyla M. Morphological characterisitcs of the immune system ofgans of young cattle raised in the polluted radioactive territory

. The object of investigation is the raising of young cattle on the farms which are located in the third zone of radioactive pollution. The goal of the work is to define morpho-functional state of the animal's immune system organs. The methods of the investigation are: clinico-anatomical, radiological, hematological, histologic, histochemical, morphometrical by means of necessary reagents and devices which have come through certain standartization. The complex investigation on the macro- and microscopic levels showed structural and functional state of thymus, spleen and some lymphatic nodes of three age groups of animals. The received relative and absolute indices of the main morphological structures of the investigated organs testify the negative influence of the ionizing radiation on the cattle body. Thus, immunocompetent organs, especially thymus, of the young animals are more susceptible to the long influence of low dose radiation than those of older ones. The spleen and lymphatic nodes parenchymashowed the deficiency of immunocompetent cells and the morphological indices were at the low point of the norm. The results of the investigation are applied in the curriculum programs and researches at the chairs of the pathological anatomy at the faculties of veterinary medicine of most higher educational establishments of Ukraine and can bealso used during the working cut of scientifically based medical and prophilactic measures as to the young of cattle raised under the conditions of the constant action of low radiation doses.